1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4 */
5
6#include <asm/asm.h>
7#include <asm/asmmacro.h>
8#include <asm/export.h>
9#include <asm/regdef.h>
10
11.macro fixup_ex from, to, offset, fix
12.if \fix
13	.section .fixup, "ax"
14\to:	addi.d	a0, a2, \offset
15	jr	ra
16	.previous
17.endif
18	.section __ex_table, "a"
19	PTR	\from\()b, \to\()b
20	.previous
21.endm
22
23/*
24 * unsigned long __copy_user(void *to, const void *from, size_t n)
25 *
26 * a0: to
27 * a1: from
28 * a2: n
29 */
30SYM_FUNC_START(__copy_user)
31	beqz	a2, 3f
32
331:	ld.b	t0, a1, 0
342:	st.b	t0, a0, 0
35	addi.d	a0, a0, 1
36	addi.d	a1, a1, 1
37	addi.d	a2, a2, -1
38	bgtz	a2, 1b
39
403:	move	a0, a2
41	jr	ra
42
43	fixup_ex 1, 4, 0, 1
44	fixup_ex 2, 4, 0, 0
45SYM_FUNC_END(__copy_user)
46
47EXPORT_SYMBOL(__copy_user)
48